The resulting closed-loop system is illustrated in
Figure 3, where the process and controller models are
denoted by GðsÞ and KðsÞ, respectively. Most of the
control approaches considered herein are presented in
continuous time for notational convenience. Hence, the
resulting controllers are discretized with a suitable
method. In this study, the ZOH-discretization with
the sampling rate of 5 kHz is applied, which is sufficient
to prevent the aliasing of the disturbances. The resulting
control scheme is general, hence enabling a reliable
comparison of the methods independent of their initial
design approaches.